1. Field of the Invention
The present invention relates to a microbicidal/microbistatic composition for industrial use and its use. More particularly, it relates to a microbicidal/microbistatic composition for industrial use and a method of killing or inhibiting the growth of microorganisms, which can be used for microbicidal/microbistatic treatment of papermaking process water in paper and pulp industry, cooling water or washing water for various industries, heavy oil sludges, cutting oils, textile oils, paints, antifouling coatings, paper coating liquids, latices, sizings or the like.
2. Description of the Prior Art
It has been known that in papermaking process water of paper and pulp industry and cooling water of various industries, slimes are generated due to the growth of bacteria and/or fungi and results in such problems as lowering of the quality of products and the efficiency of production. Further, in many industrial products, for example heavy oil sludges, cutting oils, textile oils, paints, various latices, and sizings, putrefaction and contamination occur due to the growth of bacteria and fungi to reduce their value.
Thus, many microbicidal agents have been used in order to prevent the problems induced with such microorganisms. Formerly, organomercury compounds, chlorinated phenol compounds and the like were used for this purpose. But, these compounds generally show strong toxicity to human body, fishes and shellfishes, and cause environmental contamination. Therefore, their use comes to be regulated. Recently, relatively low toxic compounds such as described below have been generally used as microbicidal compounds for industrial use, namely, organonitrogene-sulfur compounds such as methylene bisthiocyanate, 1,2-benzoisothiazoline-3-one and 5-chloro-2-methyl-4-isothiazoline-3-one; organobromine compounds such as 2,2-dibromo-2-nitroethanol, 2,2-dibromo-3-nitrilopropionamide, 1,2-bis(bromoacetoxy)ethane, 1,4-bis(bromoacetoxy)-2-butene and bistribromomethyl sulfone and the like; and organosulfur compounds such as 4,5-dichloro-1,2-dithiol-3-one.
Such known compounds show different microbicidal spectra and effects and are used corresponding to their working objects. For example, 4,5-dichloro-1,2-dithiol-3-one, 2,2-dibromo-2-nitroethanol, 2,2-dibromo-3-nitrilopropionamide, bistribromomethylsulfone and the like exhibit an action that their addition even in a small amount remarkably decreases the number of viable bacteria, which is referred to as "microbicidal action" hereafter, but they are not potent in the action of inhibiting the growth of viable bacteria for a long period of time, which is referred to as "antimicrobial (microbistatic) action". Further, methylene bisthiocyanate, 1,2-bis (bromoacetoxy)ethane, 1,4-bis(bromoacetoxy)-2-butene and the like have a microbistatic action, but are required to maintain in a high concentration for a long period in order to exert their microbicidal action.
Therefore, the above mentioned ingredients are often used in a manner of their appropriate combination and this can sometimes develop a synergistic effect. But the effective combinations are limited in number. In addition, it is also known that when a composition containing a single ingredient is continuously used, resistant bacteria occur to decrease the effect of the composition.
Further, the temperature of industrial process water or industrial products to be subjected to a microbicidal/microbistatic treatment will greatly vary depending on seasons or working factors. For example, the temperature of papermaking process water is about 40.degree. C. in summer but drops into 15.degree. C. or lower in winter. Such temperature drop is known to be generally a factor remarkably reducing microbicidal/microbistatic effects of bactericidal compounds.
The present invention was made under the above circumstances, and its purpose is to provide a composition which can exhibit sufficient microbicidal/microbistatic action in a smaller amount and can maintain its effects even at lower temperature.
Nitrobromopropane derivatives of the formula (I) as mentioned below are known from the disclosures in Japanese Published Examined Patent Application No. 16460/1968, EPA No. 36055 and EPA No. 34684 to have solely a microbicidal activity but they are not known to exhibit a synergistic effect by combination use with other agent(s) and maintain this effect even at low temperature.
On the other hand, 4,5-dichloro-1,2-dithiol-3-one as disclosed in for example U.S. Pat. Nos. 4,334,957 and 4,647,577, etc., is known to have a microbicidal effect by itself and also exert a synergistic effect by the specific combination use with some agents. However, the combination use of the above compound and the nitrobromopropane derivatives of the formula (I) is not known.